Just like a hostname can be changed, a MAC address can also be changed through...

MAC spoofingallows attackers tochange their network identity, making tracking harder.Cybercriminals use it to:

Bypass network security measures(e.g., MAC filtering).

Evade law enforcement trackingin cyber investigations.

Appear as another devicein network logs.

References:McAfee Institute CCII Cyber Threat Guide, The Hitchhiker’s Guide to Online Anonymity​.